how to remove or reset the service engine soon light? on 1998 Nissan Altima

my nissan altima 1998 model is newly tuned up but the service engine soon light still appears.the light appears a day ago and we tuned up the engine right after.

Asked by for the 1998 Nissan Altima
It does not mean the car needs a maintenance service, but there is an engine or emission control problem is registered into the engine control module, it has to be diagnosed by a diagnostic computer and repaired accordingly. After the repair the ECM's memory and adaptation has to be reset.